/Engine/Plugins/Runtime/GameplayAbilities/Source/GameplayAbilities/Public/GameplayEffect.h
WARNING: This will locally perform attribute changes on your client so beware.
void PredictivelyExecuteEffectSpec ( [FGameplayEffectSpec](API\Plugins\GameplayAbilities\FGameplayEffectSpec) & Spec, [FPredictionKey](API\Plugins\GameplayAbilities\FPredictionKey) PredictionKey, const bool bPredictGameplayCues )